what can I use to get the acidity out from my tomato veg soup

Puree some basil and cheese into it.

Taking this in a totally different direction . . . not sure what context is here, but as a kid, I would crumble saltines into my soup, which always made it seem less harsh. Very low brow, but oh my, how delicious. (I crumbled saltines into everything I could find, by the way. In retrospect, it was the added texture, as much as the extra salt, that drove that habit.) ;o)

adding some grated carrot

I like mixing in some greek yogurt to make it creamier and give it less bite~

I would try adding dugar. I would be afraid the milk would curdle.

simply add a pinch of sugar, will reduce the acidity, also you can use some raisins. Will give an exotic touch and make the soup much sweeter :)

Brown sugar

Are your tomatoes whole or in chunks in your soup, or pureed?

Adding baking soda reduces acidity. Adding sugar or sweet vegetables like carrots will cover the acid taste. If you do the baking soda trick, add it 1/8th tsp at a time. If you go too far, it will taste very flat. I learned that from experience. :(